Not Applicable
Not Applicable
1. Field of the Invention
The present invention relates to a wood-type golf club. More specifically, the present invention relates to a large volume golf club with a hosel liner.
2. Description of the Related Art
The trend in the golf industry has been towards larger volume golf club heads in order to provide greater forgiveness to the typical golfer, the high handicap golfer. The trend began in the early 1990s with the stainless steel BIG BERTHA(copyright) driver from the Callaway Golf Company of Carlsbad, Calif. This was followed by the titanium GREAT BIG BERTHA(copyright) driver, also from the Callaway Golf Company, and then the 290 cubic centimeter (xe2x80x9cccxe2x80x9d), titanium BIGGEST BIG BERTHA(copyright) driver, also from the Callaway Golf Company.
These large volume golf club heads have been matched with low weight shafts in order to lower the center of gravity of the golf club to provide a more forgiving golf club. As golf club heads become larger in volume, and shafts become lighter, the needs arises for reducing high stress regions to levels that shafts can withstand during golf club impact with a golf ball.
One example of the prior art is Chappell, U.S. Pat. No. 5,688,188 for a golf club. The Chappell patent discloses an iron with a ferrule composed of a thermoplastic material having a modulus of elasticity of 80-1980 pounds per square inch, a specific gravity of 1.15 to 1.22, shore hardness of 60, and an Izod strength of 3.0 to 10. Ft/lbs. The ferrule is placed within an external hosel, and the exposed end of the ferrule 21 millimeters. The preferred material is a butyrate.
Another example is Dekura, U.S. Pat. No. 5,766,089, which was originally filed in Japan in 1994 for a metal wood composed of magnesium or aluminum alloy with a hosel attaching section composed of ABS and epoxy. The rigidity of the hosel attaching section is lower than the shaft to absorb vibration and shock to thereby reduce vibrations through the shaft.
Another example is Allen, U.S. Pat. No. 5,888,149 which was originally filed in 1999 for a shortened hosel and an extended ferrule. The primary object of the Allen patent is to reduce hosel weight without sacrificing shaft support or cosmetic integrity. The Allen patent discloses a hosel with a length of 0.625 inch to 0.750 inch, and an extended ferrule composed of a high strength thermoplastic.
One of the earliest example is Offutt, U.S. Pat. No. 1,167,922, originally filed in 1914 for a golf club head with an enlargement on a tubular metal shaft to provide a fluted surface.
Yet others have used an insert for the ability to orient the shaft relative to the club. One example of such is Jackson, U.S. Pat. No. 5,839,973 for a Golf Club Head With Enlarged Hosel, originally filed in 1996. The insert of Jackson is removable thereby allowing for another insert with a different shaft orientation to be inserted into the hosel.
A further example of such an invention is Wood, et al., U.S. Pat. No. 5,851,155, which was originally filed in 1997. The Wood patent discloses a hosel that allows for customization of the face angle for a particular golfer by reorienting the club head relative to a neck member of the hosel.
Yet a further example is Kubica, U.S. Pat. No. 5,906,549 which was originally filed in 1997 for a golf club and a multitude of hosel with each hosel having a passage with a different angle relative to the club head. Each hosel has a flat portion for securing the hosel within a bore in the club head. The hosels are composed of a material softer than the club head.
The present invention provides a solution to the reducing the stress on a shaft of golf club having a high performance, large volume golf club head. The present invention is specifically directed to reducing stress levels in high stress regions of a shaft for golf club heads with internal hosels.
One aspect of the present invention is a golf club including a golf club head, a shaft and a hosel liner. The golf club head has a crown, a sole, a striking plate, a heel end, a toe end and an internal hosel. The internal hosel has a crown opening and a sole opening. The golf club head preferably has a volume in excess of 300 cubic centimeters and weighs less than 215 grams. The hosel liner has an upper portion, a lower portion and a bore therethrough. The upper portion has a greater outside diameter than the lower portion, and lower portion is positioned within the internal hosel The hosel liner has a shoulder below the upper portion, which engages the crown. The hosel liner is composed of a polymer material. The shaft has a tip end and a butt end. The tip end of the shaft is positioned through the bore of the hosel liner and through the internal hosel to the sole opening. The shaft weighs less than 85 grams.
Having briefly described the present invention, the above and further objects, features and advantages thereof will be recognized by those skilled in the pertinent art from the following detailed description of the invention when taken in conjunction with the accompanying drawings.